Genetic Link Discovered Behind Febrile Seizures in Children

Seizures are common complications that can result from infectious diseases among young children. Understanding these seizures is an important step in diagnosing and immediately treating them. A recent international study conducted by researchers from the University of Tubingen in Germany has revealed groundbreaking information on one of the most common types of epileptic seizures to strike children – febrile seizures. The study has revealed valuable information which points to a genetic source that may be the underlying cause behind these seizures, knowledge that had previously remained unknown. The research findings put forward very promising results that could help physicians diagnose possible cases and prevent febrile seizures from occurring among children.

Febrile seizures

Febrile seizures, also referred to as febrile convulsions, are epileptic seizures caused by the changes in the body temperature. They normally inflict children between the ages of 6 months to 5 years. During a fit, the body becomes entirely stiff while both the arms and legs involuntarily twitch. The child may end up loosing their bladder or bowel control, and may also start to foam at the mouth or vomit. The child’s breathing patterns become irregular and he or she may fall unconscious while their eyes stay wide open. A febrile seizure typically does not reach five minutes long, and the inflicted child returns to normal condition an hour after. Febrile seizures occur during high fevers caused mostly by a viral infection. Benzodiazepines, such as diazepam and midazolam, are the commonly prescribed medications for these kinds of seizures.

The STX1B gene

The mechanism that the researchers were able to link to febrile seizures involved the STX1B gene. The STX1B, or Syntaxin 1-B, gene is responsible for encoding the STX1B protein. Syntaxin proteins function as vesicles for transport. Syntaxin 1-B is involved in neural synaptic transmission. The researchers discovered that the likelihood of developing febrile seizures lay in the occurrence of mutations in the STX1B gene. STX1B mutations were revealed to be the possible source behind epileptic seizure attacks.

Research experiments and findings

The experiments conducted for this study were carried out as a joint effort from several universities around Germany. The researchers at Tubingen initially isolated the STX1B genetic mutations through a process known as exome sequencing, which is used to sequence specific sections of a genome. Analysis of the mutations connected them to two families with members that were especially vulnerable to both febrile seizures and epileptic fits. Upon studying more patients, the researchers discovered more STX1B mutations.

Professor Holger Lerche of the University Department of Neurology and Epileptology at Tubingen noted that these findings could indicate a connection between STX1B mutations and epilepsy in general. Experts from the Universities of Leuven and Luxembourg conducted further experiments on STX1B mutations using zebrafish as models, for the similarities between their organ development and that of humans. One of the principal investigators, Camila Esguerra, discovered that inputting the zebrafish with genes that were genetically altered produce the expected epileptiform attacks. In addition, the brainwave activities of the zebrafish were compromised by hyperthermia, similar to instances of fever.

Further studies by genetic experts

Many genetic experts are banding together to continue research on the possible mechanisms behind epilepsy. The EuroEPINOMICS Consortium is furthering studies on epilepsy and is geared toward discovering new methods for treatment. The IonNeurONet network is also conducting research on epilepsy and is attempting to gain more information on other types of nervous system disorders. The German Federal Ministry for Education and Research is funding these collective efforts and is helping to gather patients with confirmed STX1B mutations that are willing to volunteer for experiments and test studies.